COARCTATION OF THE AORTA
The "coarctation" is a narrowing of the aorta, typically found just after the vessels are given off to the left arm. This is a cause of high blood pressure, as the kidneys do not "see" as high of a blood pressure as they would like. This leads them to release substances to raise the pressure, but it only rises substantially in the part of the circulation before the blockage. In this fashion, the heart and brain are still subjected to the very high pressures induced by the kidney’s desire for more blood.
This can cause no symptoms, and be discovered as part of the evaluation for high blood pressure when the person is in their teens, twenties, or beyond. The key finding is elevated blood pressure in the arms, with low blood pressure in the legs. Pulses in the leg may be decreased in intensity, or delayed compared with their occurrence in the arm.
Coarctations generally require repair. Dilating the segment with balloons is a possibility, particularly in the young. Surgical removal of the narrowed segment may need to be accomplished. If allowed to persist, the high blood pressure which is induced may become "permanent" even after removal of the segment due to changes in some organs which are irreversible.
Other abnormalities may co-exist, particularly abnormalities of the aortic valve. It is quite common, accounting for about 15-20% of cases of congenital heart disease, and is more common in men than in women.